package com.itxialu.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itxialu.reggie.common.BaseContext;
import com.itxialu.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否登录过滤器
 *
 * @author shkstart
 * @create 2022-09-26 21:42
 */
@Slf4j
@Component
@WebFilter(filterName = "LoginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    //路径匹配器
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        Filter.super.init(filterConfig);
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest request2 = (HttpServletRequest) request;//类型转换
        HttpServletResponse response2 = (HttpServletResponse) response;//类型转换

        //1、获取本次请求的URI
        String requestURI = request2.getRequestURI();
        log.info("本次请求路径为：{}", requestURI);

        //2、判断本次请求是否需要处理
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };
        boolean check = check(urls, requestURI);

        //3、如果不需要处理，则直接放行
        if (check) {
            log.info("本次请求{}不需要处理", requestURI);
            chain.doFilter(request2, response2);
            return;
        }
        //4-1、判断登录状态，如果已登录，则直接放行--网页端
        Long empId = (Long) request2.getSession().getAttribute("employee");
        if (empId != null) {
            log.info("用户已登录，用户id为：{}", empId);

            BaseContext.setCurrentId(empId);//把用户id放到线程封装类


            chain.doFilter(request2, response2);
            return;
        }

        //4-2、判断登录状态，如果已登录，则直接放行--移动端
        Long userId = (Long) request2.getSession().getAttribute("user");
        if (userId != null) {
            log.info("用户已登录，用户id为：{}", userId);

            BaseContext.setCurrentId(userId);//把用户id放到线程封装类


            chain.doFilter(request2, response2);
            return;
        }

        log.info("用户未登录");
        // 5、如果未登录则返回未登录结果,通过输出流向客户端页面响应数据
        response2.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    //路径匹配的方法
    private boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }

    @Override
    public void destroy() {
        Filter.super.destroy();
    }
}
